Clamp



Jude 23, 1931.

G. E. PALMER 1,811,518

CLAMP Fild Sept. 28, 1929 Patented June 23, 1931 entree STATES GEORGE E. PALMER, OFCEDAR RAPIDS, IOWA CLAMP Application filed September 28, 1929. Serial No. 395,955

This invention relates to hand clamps, and

the object of the invention is to produce a clamp having a wide range of movement and adapted for quick adjustment to any desired space between the jaws.

Other advantages incident to the construction will appear in the description and claims following, reference being had to the accompanying drawings, in which:

Fig. 1 is a side elevation of a clamp embodying the invention. Fig. 2 is a similar view illustrating a double-jaw clamp. Fig. 3 is a similar view of the improved clamp, with a bench support for the same, Fig. 4 15 is a plan view of the clamp shown in Fig. 8,

as seen from the right. Fig. 5 is a centrally sectional view of the type of clamp shown in Figs. 3 and 4:.

In the drawings, the numeral 5 denotes an the abutment jaw otherwise designated as the fixed jaw. This is to be understood in a relative sense, however, as it is adjustable, and in one type as easily and quickly adjustable as the other. In use, however, it is ordinarily the stationary jaw, the other being slid up to the work disposed between them. It is provided with a broad flat face at 6, prefer ably circular or oval to form a seat for the work to be clamped.

The cooperating jaw 7 is provided with a hand-screw 8, and on the end of the screw is swivel'ed a clamping plate 9 of substantially the same shape as the expanded face of the fixed jaw. In general, however this plate is extended downwardly and forked at 10 to straddle the main connecting bar 11 on which the jaws are mounted. Both jaws are mortised to receive the bar, which as will be noted has smooth sides and edges, so that in the case of the clamp shown in Fig. 1 both clamp members may be slid inwardly by merely pressing them in that direction. The same is true of the clamp shown in Fig. 2, when the set-screw 12 is loosened.

The mounting of the jaws on the bar is best shown in Fig. 5. The fastening of the fixed jaw bya set-screw is so simple as to need no explanation. The opposite jaw has a wider mortise for the bar, with a recess at 13 to re ceive a stirrup-shaped spring 14 tending to force the inner and lower part of the aw upwardly into contact with the bar. By tipping the upper part of the jaw inwardly the jaw may be easily retracted, and merely pushing it will move it in the opposite, inward direction.

To give the unfixed jaw a holding grip when in clamping position it is provided with two set-screws, 15 and 16, respectively, the former set in a lug 17 at the outer and upper part of the jaw member, and the other set diagonally opposite thereto in the lower part of the same member. The screw 16 is preferably-made adjustable, so that the face of the jaw may be squared with respect to the bar, or inclined thereto, as desired. A set-nut 18 fixes it securely in position. The screws beingof the regular cup-ended and hardened type, it is evident that an outward strain on the jaw will cause it to grip both edges of 70 the bar and the sharp edges of the screw tips will only bite deeper as the pressure is increased.

Figs. 3 and 4: illustrate a construction whereby the clamp may be mounted on a bench or post and serve as a hand vise. One side of the fixed aw is provided with a recess 19 adapted to receive a bar, to which it is attached by a pin 20 through holes in the jaw and bar. The bar may be of the same sort as the connecting bar 11, but is herein shown as a combination tool serviceable as a bench-dog and a wrench for the set-nut and set-screw of the clamp. Thisis shown screwed to a bench 21, when the attached, outlying clamp functions as a small fixed vise.

In Fig. 1 the clamp is shown as in clamping a'pair of boards for gluing their edges together. In Fig. 2 an irregular frame is shown as held by the double clamp which accommodates itself to the pitch of one side of the frame. The pitch of the lower screw, however, is mainly to facilitate the turning of the thumb-screw.

The speed with which the clamp may be shifted to any point along the connecting bar renders the clamp very convenient for many uses, both in wood and metal.

The spring 14 is not indispensable, since the aw may be tipped outwardly by hand to gripping position and will then hold on the ar when pressure is applied. It is, however; much more convenient to have the jaw held automatically and elastically to position to grip the bar, and the use of the spring for this purpose is therefore desirable.

Itis' to be noted furthermore that the recess for the tension spring is formed to positively retain the spring in its place,vso that m in shifting the jaw from one bar to another the spring does not drop out. This is done by turning a lip 23 in under the bend of the spring to form a socket for that portion of the spring, and providing a lug 24 to take the end of the upper leaf of the spring.

Having thus described 'my invention, I 01mm:

1. In a hand-clamp, the combination of a V smooth-edged bar, an abutment jaw attachable to the bar and provided with a lateral seat for another bar at an angle to the firstmentioned bar,-a companion jaw slidable on the bar, and having diagonally disposed bargripping members at opposite sides of the 25 bar, a compression screwand head carried by the slidable aw, and means for attaching the secondary bar to a fixed support, and the connected head to said bar.

2; In a'hand-clamp, the combination of a smooth-edged bar, an abutment jaw fixedly attachable to the bar, anda cooperating slidable jaw 'mortised to admit the bar, andprovided with sharp-ended,bar-engaging setscrews disposedat diagonally opposite sides of themortise, said first mentioned jaw having a slide-wayflupon one'side thereof arranged'at an angle to the opening for the bar and adapted to receive an auxiliary bar whereby the clamp may be mounted on a 40 comparatively fixed support. 3. In a tool of "he character indicated, a jaw having awork-engaging head and a body, said body being apertured transversely for the reception of a supporting bar and a bar engaging spring, the aperture for the spring having at oneend a socketto receive a portion of the spring, the Wall of the body overhanging a portion of the spring on the side adjacent the bar, there being a'lug I so located at the other end of'the aperture to cooperate with'lthe overhanging portion of the wall inholding the spring in the socket. I In testimony-whereof I affix my signature.

,GEORGE E. PALMER. 

